1. Field of the Invention
The subject invention relates generally to a battery pack assembly with an integrated heater.
2. Description of the Prior Art
Battery packs that contain lithium ion batteries are increasingly popular with automotive applications and various commercial electronic devices because they are rechargeable and have no memory effect. Storing and operating a lithium ion battery at an optimal operating temperature is very important to allow the battery to maintain a charge for an extended period of time. Due to the characteristics of lithium ion batteries, the battery pack operates within an ambient temperature range of −20° C. to 60° C. However, even when operating within this temperature range, the battery pack may begin to lose its capacity or ability to change or discharge should the ambient temperature fall below 0° C. Depending on the ambient temperature, the life cycle capacity or charge/discharge capability of the battery may be greatly reduced as the temperature strays below 0° C. Nonetheless, it may be unavoidable that a lithium ion battery be used where the ambient temperature falls outside an optimum temperature range of 0 to 60° C.
But even to the extend of being effective in certain respects, there remains an opportunity to improve upon the lithium ion batteries of the prior art to increase the ambient temperature range at which the lithium battery operates. Also, there remains an opportunity to maintain the battery pack at the optimal operating temperature to ensure the longest possible life cycle, rated capacity, and nominal charge and discharge rates.